METHOD FOR PRODUCING ESTER COMPOUND

Abstract

What is provided is a production method in which a vinyl acetate is reacted with a primary or secondary alcohol represented by Formula (1) and carbon monoxide to produce a first ester compound represented by Formula (2), and the first ester compound is reacted with an alcohol to produce a lactic acid ester represented by Formula (3) and an acetic acid ester represented by Formula (4).

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Claims

1. A method for producing an ester compound, comprising: a first step of reacting a vinyl acetate with a primary or secondary alcohol represented by General Formula (1) and carbon monoxide in a presence of a first catalyst to produce a first ester compound represented by General Formula (2); and a second step of reacting the first ester compound with an alcohol in a presence of a second catalyst to produce a lactic acid ester represented by General Formula (3) and an acetic acid ester represented by General Formula (4), ##STR00016## (in Formulae (1) to (4), le is a hydrocarbon group which has 1 to 10 carbon atoms and may have an alicyclic ring or an aromatic ring in part or in whole, R.sup.1's in Formula (1) and Formula (2) are the same, and R.sup.1's in Formula (3) and Formula (4) are the same).

2. The method for producing an ester compound according to claim 1, further comprising, before the second step: an intermediate step of reducing an unreacted vinyl acetate included in a reaction solution after the first step to convert the unreacted vinyl acetate into an acetic acid ester.

3. The method for producing an ester compound according to claim 2, wherein, in the intermediate step, an acetaldehyde included in the reaction solution after the first step is hydrogenated to be converted into ethanol, and in the second step, the first ester compound in the reaction solution after the intermediate step is reacted with the ethanol in the presence of the second catalyst.

4. The method for producing an ester compound according to claim 1, wherein the primary or secondary alcohol represented by General Formula (1) is ethanol.

5. The method for producing an ester compound according to claim 1, wherein the first catalyst includes a compound having at least one element selected from Periodic Table Group 10 elements, and an organic phosphine ligand.

6. The method for producing an ester compound according to claim 5, wherein the Periodic Table Group 10 element is Pd.

7. The method for producing an ester compound according to claim 5, wherein the organic phosphine ligand is a monodentate organic phosphine ligand.

8. The method for producing an ester compound according to claim 7, wherein the organic phosphine ligand is an organic phosphine ligand represented by General Formula (5), ##STR00017## (in Formula (5), R.sup.3 and R.sup.4 are alkyl groups having 1 to 6 carbon atoms, cycloalkyl groups having 6 to 9 carbon atoms, or aryl groups having 6 to 9 carbon atoms, R.sup.3 and R.sup.4 may be the same or different from each other, R.sup.5 to R.sup.9 are hydrogen atoms, alkyl groups having 1 to 4 carbon atoms, alkoxy groups having 1 to 4 carbon atoms, or dialkylamino groups having 2 to 8 carbon atoms, and R.sup.5 to R.sup.9 may all be the same or may be partially or completely different from each other).

9. The method for producing an ester compound according to claim 1, wherein the first catalyst includes an acidic compound.

10. The method for producing an ester compound according to claim 9, wherein the acidic compound is at least one selected from the group consisting of an alkyl sulfonic acid, an ammonium salt of an alkyl sulfonic acid, a pyridinium salt of an alkyl sulfonic acid, an aryl sulfonic acid, an ammonium salt of an aryl sulfonic acid, and a pyridinium salt of an aryl sulfonic acid.

11. The method for producing an ester compound according to claim 1, wherein the first catalyst includes a nitrogen atom-containing heterocyclic compound.

12. The method for producing an ester compound according to claim 11, wherein the nitrogen atom-containing heterocyclic compound is at least one selected from the group consisting of pyridine and picoline.

13. The method for producing an ester compound according to claim 1, wherein the second catalyst is at least one selected from the group consisting of potassium carbonate, sodium methoxide, sodium ethoxide, sodium-t-butoxide, potassium ethoxide, tetraethoxytitanium, tetraisopropoxytitanium, tetra-n-butoxytitanium, mono-n-butyltin oxide, di-n-butyltin oxide, di-n-butyltin laurate, and di-n-octyltin oxide.

14. The method for producing an ester compound according to claim 1, further comprising: before the first step, a carbon monoxide producing step of pyrolyzing a plastic or a biomaterial to produce carbon monoxide.

15. The method for producing an ester compound according to claim 4, wherein the ethanol is bioethanol derived from a plant.

16. A method for producing an ester compound, comprising: a first step of reacting a vinyl acetate with a primary or secondary alcohol represented by General Formula (1) and carbon monoxide in a presence of a first catalyst to produce a first ester compound represented by General Formula (2), wherein the first catalyst includes a compound having at least one element selected from Periodic Table Group 10 elements, and an organic phosphine ligand represented by General Formula (5), ##STR00018## (in Formulae (1) and (2), R.sup.1 is a hydrocarbon group which has 1 to 10 carbon atoms and may have an alicyclic ring or an aromatic ring in part or in whole, and R.sup.1's in Formula (1) and Formula (2) are the same) (in Formula (5), R.sup.3 and R.sup.4 are alkyl groups having 1 to 6 carbon atoms, cycloalkyl groups having 6 to 9 carbon atoms, or aryl groups having 6 to 9 carbon atoms, R.sup.3 and R.sup.4 may be the same or different from each other, R.sup.5 to R.sup.9 are hydrogen atoms, alkyl groups having 1 to 4 carbon atoms, alkoxy groups having 1 to 4 carbon atoms, or dialkylamino groups having 2 to 8 carbon atoms, and R.sup.5 to R.sup.9 may all be the same or may be partially or completely different from each other).

17. The method for producing an ester compound according to claim 16, wherein the primary or secondary alcohol represented by General Formula (1) is ethanol.

18. The method for producing an ester compound according to claim 16, wherein the Periodic Table Group 10 element is Pd.

19. The method for producing an ester compound according to claim 16, wherein, in General Formula (5), R.sup.3 and R.sup.4 are cyclohexyl groups, R.sup.5 and R.sup.9 are methoxy groups, and R.sup.6 to R.sup.8 are hydrogen atoms.

20. The method for producing an ester compound according to claim 16, wherein the first catalyst includes an acidic compound.

21. The method for producing an ester compound according to claim 20, wherein the acidic compound is at least one selected from the group consisting of an alkyl sulfonic acid, an ammonium salt of an alkyl sulfonic acid, a pyridinium salt of an alkyl sulfonic acid, an aryl sulfonic acid, an ammonium salt of an aryl sulfonic acid, and a pyridinium salt of an aryl sulfonic acid.

22. The method for producing an ester compound according to claim 16, wherein the first catalyst includes a nitrogen atom-containing heterocyclic compound.

23. The method for producing an ester compound according to claim 22, wherein the nitrogen atom-containing heterocyclic compound is at least one selected from the group consisting of pyridine and picoline.

Description

EXAMPLES

[0225] Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The present invention is not limited to Examples described below.

Example 1

[First Step]

[0226] To a stainless steel reaction vessel with a capacity of 40 mL, PdCl.sub.2 (palladium chloride; manufactured by Soekawa Chemical Co., Ltd.: 3.0 mg, 17.01 pmol) as the compound having at least one element selected from Periodic Table Group 10 elements, which is the first catalyst, triphenylphosphine (manufactured by Tokyo Chemical industry Co., Ltd.; 8.92 mg, 34.00 μmol) as the organic phosphine ligand which is the first catalyst, and PTSA (p-toluenesulfonic acid.monohydrate; manufactured by Tokyo Chemical Industry Co., Ltd.; 1.3 mg, 6.723 μmol) as the acidic compound which is the first catalyst were added.

[0227] To the reaction vessel in which these first catalysts are charged, vinyl acetate (manufactured by FUJIFILM Wako Pure Chemical Corporation; 0.75 mL, 8.1 mmol), ethanol (manufactured by FUJIFILM Wako Pure Chemical Corporation; 1.2 mL, 20 mmol) as the primary or secondary alcohol, toluene (manufactured by FUJIFILM Wako Pure Chemical Corporation; 6.75 mL) as the solvent, and pyridine (manufactured by FUJIFILM Wako Pure Chemical Corporation; 0.0275 mL, 340.2 μmol) which is the nitrogen atom-containing heterocyclic compound as the first catalyst were added under a nitrogen stream to obtain a reaction solution.

[0228] A used amount of the palladium chloride in Example 1 was 0.002 molar part with respect to 1 molar part of the vinyl acetate. A used amount of the organic phosphine ligand was 2 molar parts with respect to 1 molar part of the palladium chloride. A used amount of PTSA (p-toluenesulfonic acid.monohydrate) was 0.395 molar parts of acid point of PTSA with respect to 1 molar part of the palladium chloride. A used amount of the pyridine was 20 molar parts with respect to 1 molar part of the palladium chloride.

[0229] In addition, a used amount of the toluene was 0.83 liters (amount in which the concentration of the vinyl acetate in the reaction solution was 1.2 mol/liter) with respect to 1 molar part of the ethanol.

[0230] Next, using a carbon monoxide gas, pressurization and depressurization in the reaction vessel was repeated 3 times between atmospheric pressure and 1 MPa, and the gas inside the reaction vessel was replaced with the carbon monoxide gas. Thereafter, the pressure inside the reaction vessel was increased to 5 MPa using the carbon monoxide gas, and the reaction solution was reacted at 100° C. for 15 hours while stirring to produce a first ester compound.

[0231] The reaction solution after the reaction was analyzed using gas chromatography (device name: 6850GC, manufactured by Agilent Technologies, Inc.). Quantitative analysis of the raw material, the first ester compound which is the target product, and the side reaction product was performed by creating a calibration curve using diethylene glycol dimethyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.) as an internal standard substance.

[0232] As a result, in the first step of Example 1, it was confirmed that the first ester compound in which R.sup.1 in General Formula (2) was an ethyl group was produced. A conversion rate of the vinyl acetate was 29%, the yield of the first ester compound based on the vinyl acetate used in the first step was 26%, and the yield of the ethyl acetate based on the vinyl acetate used in the first step was 3%.

[0233] [Intermediate Step]

[0234] 10 mg of a catalyst (manufactured by N.E. CHEMCAT CORPORATION) in which palladium was supported on a carrier consisting of activated carbon by 5 parts by mass with respect to 100 parts by mass of the carrier was added to the reaction solution after the first step as a catalyst. Thereafter, using a nitrogen gas, pressurization and depressurization in the reaction vessel was repeated 3 times between atmospheric pressure and 1 MPa, and the gas inside the reaction vessel was replaced with the nitrogen gas. Thereafter. the inside of the reaction vessel was set to a hydrogen gas atmosphere of 0.8 MPa, and the reaction was carried out at room temperature (20° C.) for 15 hours to reduce unreacted vinyl acetate included in the reaction solution.

[0235] In the same manner as in the reaction solution after the first step, the reaction solution after the reaction was analyzed using gas chromatography (device name: 6850GC, manufactured by Agilent Technologies, Inc.).

[0236] As a result, it was confirmed that the vinyl acetate disappeared and the ethyl acetate was produced by performing the intermediate step in Example 1. The yield of the first ester compound after the intermediate step based on the vinyl acetate used in the first step was 26%, and the yield of the ethyl acetate based on the vinyl acetate used in the first step was 71%.

[0237] [Second Step]

[0238] Using an evaporator. low boiling point compounds (boiling point of 120° C. or lower) such as ethanol, ethyl acetate, and toluene were recovered and removed from the reaction solution after the intermediate step. From the reaction solution after the intermediate step, in which the low boiling point compounds had been removed, the first ester compound was isolated using a silica column (manufactured by FUJIFILM Wako Pure Chemical Corporation) using ethyl acetate as an eluent.

[0239] The isolated first ester compound (41.6 mg, 0.26 mmol), ethanol dried in advance with Molecular Sieve 3A (manufactured by UNION SHOWA K.K.) (3 ml, 0.051 mol), and potassium carbonate (400 mg, 2.9 mmol) as a catalyst were added to an eggplant-shaped flask, and the reaction was carried out by stirring the mixture at room temperature (20° C.) and normal pressure for 1 hour.

[0240] In the same manner as in the reaction solution after the first step, the reaction solution after the reaction was analyzed using gas chromatography (device name: 6850GC, manufactured by Agilent Technologies, Inc.). Quantitative analysis of the lactic acid ester represented by General Formula (3) and the acetic acid ester represented by Cieneral Formula (4), which are the target products, and the side reaction product was performed by creating a calibration curve using diethylene glycol dimethyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.) as an internal standard substance.

[0241] As a result, it was confirmed that, by performing the second step of Example 1, the lactic acid ester represented by General Formula (3), in which R.sup.1 was an ethyl group, and the acetic acid ester represented by General Formula (4), in which R.sup.1 was an ethyl group, were produced. The yield of the lactic acid ester based on the first ester compound used in the second step was 63%, and the yield of the acetic acid ester based on the first ester compound used in the second step was 62%.

Example 2

[0242] [First Step]

[0243] The first step was performed in the same manner as in Example 1, except that 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl represented by Formula (5-1) (SPhos; manufactured by Sigma-Aldrich Japan; 14.0 mg, 0.034 mmol) was used as the organic phosphine ligand which is the first catalyst, and methanol (manufactured by FLA IFIL,M Wako Pure Chemical Corporation; 0.81 mL; 20 mmol) was used as the primary or secondary alcohol.

[0244] Same as Example 1, the reaction solution after the reaction was analyzed using gas chromatography (device name: 6850GC, manufactured by Agilent Technologies, Inc.).

[0245] As a result, in the first step of Example 2, it was confirmed that the first ester compound in which R.sup.1 in General Formula (2) was a methyl group was produced. A conversion rate of the vinyl acetate was 95%, the yield of the first ester compound based on the vinyl acetate used in the first step was 79%, and the yield of the methyl acetate based on the vinyl acetate used in the first step was 9%.

[0246] [Second Step]

[0247] Using an evaporator, low boiling point compounds (boiling point of 120° C. or lower) such as methanol, methyl acetate, and toluene were recovered and removed from the reaction solution after the first step. From the reaction solution after the first step, in which the low boiling point compounds had been removed, the first ester compound was isolated using a silica column (manufactured by FUJIFILM Wako Pure Chemical Corporation) using ethyl acetate as an eluent.

[0248] The isolated first ester compound (43.8 mg, 0.30 mmol), methanol dried in advance with Molecular Sieve 3A (manufactured by UNION SHOWA K.K.) (3 ml, 0.074 mol), and potassium carbonate (400 mg, 2.9 mmol) as a catalyst were added to an eggplant-shaped flask, and the reaction was carried out by stirring the mixture at room temperature (20° C.) and normal pressure for 1 hour.

[0249] In the same manner as in the reaction solution after the second step of Example 1, the reaction solution after the reaction was analyzed using gas chromatography (device name: 685000, manufactured by Agilent Technologies, Inc.).

[0250] As a result, it was confirmed that, by performing the second step of Example 2, the lactic acid ester represented by General Formula (3), in which R.sup.1 was a methyl group, and the acetic acid ester represented by General Formula (4), in which R.sup.1 was a methyl group, were produced. The yield of the lactic acid ester based on the first ester compound used in the second step was 75%, and the yield of the acetic acid ester based on the first ester compound used in the second step was 76%.

Example 3

[0251] [First Step]

[0252] The first step was performed in the same manner as in Example 1, except that 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl represented by Formula (5-1) (SPhos;

[0253] manufactured by Sigma-Aldrich Japan; 14.0 mg, 0.034 mmol) was used as the organic phosphine ligand which is the first catalyst.

[0254] Same as Example 1, the reaction solution after the reaction was analyzed using gas chromatography (device name: 6850GC, manufactured by Agilent Technologies, Inc.).

[0255] As a result, in the first step of Example 3, it was confirmed that the first ester compound in which R′ in General Formula (2) was an ethyl group was produced. A conversion rate of the vinyl acetate was 96%, the yield of the first ester compound based on the vinyl acetate used in the first step was 85%, and the yield of the ethyl acetate based on the vinyl acetate used in the first step was 7%.

[0256] [Intermediate Step]

[0257] 50 mg of a catalyst (manufactured by N.E. CHEMCAT CORPORATION) in which palladium was supported on a carrier consisting of activated carbon by 10 parts by mass with respect to 100 parts by mass of the carrier was added to the reaction solution after the first step as a catalyst, and the intermediate step was performed in the same manner as in Example 1.

[0258] In the same manner as in the reaction solution after the first step, the reaction solution after the reaction was analyzed using gas chromatography (device name: 6850GC, manufactured by Agilent Technologies, Inc.).

[0259] As a result, it was confirmed that the vinyl acetate disappeared and the ethyl acetate was produced by performing the intermediate step in Example 3. The yield of the first ester compound after the intermediate step based on the vinyl acetate used in the first step was 84%, and the yield of the ethyl acetate based on the vinyl acetate used in the first step was 12%.

[0260] [Second Step]

[0261] The reaction solution after the intermediate step (7.0 g, containing 1090 mg of the first ester compound), ethanol dried in advance with Molecular Sieve 3A (manufactured by UNION SHOWA K.K.) (2.0 ml, 34 mmol), and potassium carbonate (1000 mg, 7.2 mmol) as a catalyst were added to an eggplant-shaped flask, and the reaction was carried out by stirring the mixture at room temperature (20° C.) and normal pressure for 1 hour.

[0262] In the same manner as in the reaction solution after the second step of Example 1, the reaction solution after the reaction was analyzed using gas chromatography (device name: 6850GC, manufactured by Agilent Technologies, Inc.).

[0263] As a result, it was confirmed that, by performing the second step of Example 3, the lactic acid ester represented by General Formula (3), in which R.sup.1 was an ethyl group, and the acetic acid ester represented by General Formula (4), in which R.sup.1 was an ethyl group, were produced. The yield of the lactic acid ester based on the first ester compound used in the second step was 86%, and the yield of the acetic acid ester based on the vinyl acetate used in the first step was 98%.